1. Field of the Invention
The present invention relates to a fluid moving system whereby the movement of such fluid is from the producing formation elevation of a shallow well to the earth's surface. The more specific intended application of the herein described invention encompasses a downhole air lift pumping assembly utilizing pressurized air supplied by an air compressor through a photo-voltaic programmable control system which supplies artificial lift air to oil from its sub-surface formation through production tubing suspended in a well bore and casing to the earth's surface and storage.
2. Background Art
Many shallow oil wells do not initially contain sufficient reservoir pressure necessary to provide natural lift of the oil and any associated fluids from the sub-surface producing formation level to the earth's surface. When this condition exists, it becomes necessary to utilize equipment and methods known as "artificial lift" to accomplish movement of the oil fluids from the well to the surface.
The type of pumping method selected for this artificial lift is determined by differing factors such as: production rate, well depth, well cleanliness, oil viscosity, economics of production, and others.
The most common lift method utilized today is the reciprocating sucker-rod and jack technique which incorporates a piston/ball mechanical pump located in production tubing at the producing formation level.
Other types of lift systems sometimes used are the submersible and screw type pump located downhole in the well bore; gas lift valves on production tubing; and the bailer or wick type pump.
Each of these systems has its specific technique of employing lift; however all have common disadvantages in operation and well economics. Each system, excluding gas lift valves, produces friction losses and internal wear. Gas lift valves on the other hand, require higher reservoir pressure for proper operation which most shallow wells commonly lack. All of the above systems require high capital expenses upon initial installation due in part to the system design and mechanical equipment required for operation. They historically also require large amounts of professional workover maintenance expense simply to keep in operation.
Giving consideration to the characteristics associated with these various pumping systems, it becomes unfeasible to drill, complete, and then produce many low volume shallow oil wells primarily due to the previously mentioned economic expenditures of equipping such a well and then the associated excessive mechanical expenses required to maintain it in operation.
In view of this, there would be a significant advantage to shallow oil operations if an efficient, economical, easily installed and maintenance reduced lift system could be provided.